WASHINGTON (AP) — President Barack Obama signed legislation Friday maintaining jobs on transportation projects and preventing interest rate increases on new loans to millions of college students, saying it would “make a real difference” for millions of Americans.

Obama, flanked by unemployed construction workers, college students and members of Congress at the White House, said he was hopeful that “this bipartisan spirit spills over into the next phase” on measures to boost the economy.

“There’s no excuse for inaction when there are so many Americans still trying to get back on their feet,” Obama said. He said the transportation and education measures “will make a real difference in the lives of millions of Americans.” Obama signed the bill following a two-day bus trip through parts of Ohio and Pennsylvania.

Congress approved the legislation last week after Obama made the expiring student loan interest rates an issue for months, appealing to college students and young voters who are a key constituency for his re-election campaign. The legislation served as an election-year battle over which party is best equipped to help voters grapple with a sluggish economy, the top issue.

The bill allows more than $100 billion to be spent on highway, mass transit and other transportation programs during the next two years. The projects would have expired June 30.

It also keeps interest rates of 3.4 percent for subsidized Stafford loans for undergraduates. If Congress hadn’t acted, the rate would have doubled beginning July 1 for an estimated 7.4 million students expected to get new loans this year, adding an extra $1,000 to the average cost of each loan.

In an email, White House senior adviser David Plouffe credited regular Americans for pressuring Congress to act. “You took to Twitter and Facebook. You sent emails and talked to your friends and neighbors. And in the end, your voices made all the difference,” Plouffe wrote.

The bill included unrelated measures dealing with Asian carp, roll-your-own tobacco and federal timber aid. It consolidates federal transportation programs, giving states more flexibility in spending money from Washington. It also includes safety initiatives including requirements aimed at enhancing bus safety.